Signal transmitting apparatus



Feb. 6,1940. 1.. GIRARDIN SIGNAL TRANSMITTING APPARATUS 2 Sheets-$heet 1 Filed Sept. 26, 1936 HIS ATTORNEY w E A 1 F w J T A MA v P T V n L m Feb. 6, 1940. 1.. GIRARDIN SIGNAL TRANSMITTING APPARATUS 2 Sheets-Sheet 2 Filed Sept. 26, 1936 N M 1% F EN HG, NE T 5% 5 5 1 NN SN FJNQ fiiw J 6% mJ fir n 3 u i T 3 @mi fifi fiw flJ 111s ATTORNEY 1. M .1 1 @Q g i Patented Feb. 6, 1940 2,1s9, 1 *11 p SIGNAL TRANSMITTING APrAaArUs Louis Girardin, Paris, France, assignonlby mesne assignments, to The UnionSWitch 8: Signal Company, Swissvale, Pa;

Pennsylvania,

a corporation oi Application September 26, 1936-, Serial No.102,774

In France April 10, 1936 a 40mins; (curt-380) i This invention relates to signal transmitting apparatus particularly in connection with railway and other signaling systems, and has for its chief object toprovide an improved system by means of'which a signal or indication may be given on vehicles or cars of any kind more particularly locomotives or cars on railways.

crating or braking apparatus, whenthe vehicle I to approaches shunting yards, curves, cross-overs or points.

The railway or other signaling system according to the present invention is characterized in that there are supplied to the signaling circuit current impulses comprising a code the pattern of which is determined in accordance with the operation of a group of sequentially controlled devices such, for example, as a counting relay chain.

-The signal transmitting apparatus set forth in my present application is somewhat-similar to thatset forth in the copending application of Lloyd V; Lewis, Serial No; 600,786, filedon March Inorderthat this inventionmay be the more clearly understoodand readily carried into effect, we will proceed to describe the same with reference to the accompanying drawings, which i1- lustrate by way of example and not of limitation certain convenient arrangements according to the present invention for controlling the usual signaling devices used for producing current variations-in thesignaling circuits, and in which Figure 1 is'a diagrammatic representation of a simple codin'g or modulating device for producing current variations.

Fig. 2 is adiagrammatic representation of a signaling system according to the present inventionv showing meansv for modifying the code produced by the device shown in Fig. 1.

Fig. 3 is: a diagrammatic time-table showing the sequence of operations of -the apparatus shown inFig. 2. l l

Referring now to Figure 1, the signaling circuit C shown therein comprises a single track section which is insulated from the other track sections in accordance withthe usual practice in the so-called automatic block" installations.

Thetwo rails areconnected to the ends of the secondary windingsof a transformer l, the primarywinding of which is connected to a source of alternating'current' (not shown) at DE. In

the primary circuit of the transformer I there is included a switch 2 and a current interrupting device- 3 controlled by a modulator or coder 4 which maybe of any" suitable form such,- for example, as a special relay, an oscillating circuit with or-without a thermionic valve, a rotary corrtactor,"a vibrating device or a chronographic pulsator orthe like. "The said modulator isconnected through a switch .5 to a suitable source of current or to a suitable controlling system (not shown) at the pointsA and B. The operation of this system is -as'1fo1lows-:- when the switches 2 and 5 are closed the modulator i is-brought intooperation and alternately makes and breaks the primary circuit of the transformer'l by means of the interrupting de vice 3, thereby causing' corresponding current variations or impulses to be induced in the secondary circuit and in the signaling circuit C. It will be obvious that when a vehicle or: train equipped with suitable receiving apparatus enters the track section it will receive the variations thus produced togive the" desired indications or toeffect the necessary vehicle control. e

The arrangement above described by way of example is, of course, only a simple form and it will be obvious that such an arrangement may be associated with suitable track circuit apparatus used 'to actuate wayside signals thereby giving awayside signal indication in addition to the indicationcbtained on the vehicle. The above-mentioned circuits may also be used to control the actuation of the'switches 2 and 5, for example, sothat theyare closed only on the approach of a vehicle. It is also possible to-pro vide suitable emergency or auxiliary devices with a view to obviating a'iailur'e of the feeding source or of the devices which. are normally provided,

produced by cod'er4. Forthis purpose the coder 4; is provided, inaddition to the interrupting. device 3 with two int'errupters Sand 1- capable' of being brought alternately into contact with the respective contactsii and 9. It will be apparent that when the device 3 is in one of its contact positions, contact finger Swill engage the upper contact 8 and contact finger I will be out of contact with the lower contact 9 while, when the device 3 is in its other contact position, contact finger 6 will be out of contact with the contact 8 and contact finger 'I will make contact with the lower contact 9.

One terminal B of the supply system, which in the example shown is a source of direct current, I

is connected to the coder 4' and to the supply wires of several suitable relays ll), ll, I2, l3, l4, and I5, respectively, which comprise a counting chain, the operation and function of which will be described hereinafter. With the relays of this chain are respectively associated the contacts lfla, lllb, etc., Ila, llb, etc., the numeral desig-;

nating each contact indicating the relay with which it is associated and the sufiix indicating the particular contact in question. The apparatus includes also two control relays l6 and I! having a time-constant suchthat these relays both remain energized during the normalsequential operationof the counting chain. Relays I6 and H are arranged in such a manner that relay I6 is controlled by the even-numbered relays (I0, l2, I4) while relay IT is controlled by the odd-numbered relays (I I, l3, l5). The operation of the apparatus is indicated diagrarmnatically inthe time-table of Fig. 3 and is as follows:-Assu.me first that all of the relays II] to I! are de-energized and that the coder 4 is brought into action through closing of the switch 5 in the circuit A, 5, 4, B. This will bring the finger 6 into contact with contact 8 for the first impulse whereupon thefollowing pickup circuit will be established forrelay Ill: A, 6, 8, Ilia, l'l'a, II], B. As soonas relay ill picks up, it will remain energized during the time contact 6-8 remains closed over the following stick circuit: A, 6, 8, Ila down, Illa up, III, B. Pickup of relay lll closes the following pickup circuit for the checking relay IT; A, 6, 8, Ilc, I30, I50, II, Mid, B. As soon as relay l'l picks up, it establishes an obvious stick circuitfor itself over contact l'lb. During the operation. so far described, contact 6-8 has remained closed. As soon as contact 6-8 opens, and contact 1-9 closes for the second impulse, energy is removed from relay l but this relay remainspicked up for a short interval thereafter suficient to enable relay II to pick up over the following circuit: A, l, 9, I521, lab, I I, B. Relay II will now pick up and will prepare a pickup circuit for relay l2 over front contact Ila. When relay II picks up, the circuit for relay II] which was previously interrupted at contact 6-8 is interrupted at a second point, namely at back contact I la. Pickup of relay ll closes the following pickup circuit for the checking relay I: A, I, 9, I40, I20, llic l5, Ild, B. As soon as relay l3 picks up, it closes an obvious stick circuit for itself over its front contact I612. The pickup of relay l5 completes the circuit for, the primary of transformer I over contacts 3, I60, lie, and Ho so that an impulse is transmitted to the track. a

During the timethat the contact '6-8 remains open, energy is removed from relay l1, and during the time contact 1-9 is open, energy is likewise removed from relay IS. The release time of these relays is sufficiently long, however, to bridge these open circuit intervals so that in the normal sequential operation of the counting chain, both relays I6 and I1 remain picked up.

It willbe apparent that if the cycle of operations had begun for that position of coder 4 in which finger 1 makes contact with contact 9, then no relay of the counting chain would have been energized. The cycle of operations must, therefore, always begin with the energization of the first relay II] of the series. The checking relays l6 and I! will bothremain picked up as long as proper sequential operation of the counting relays continues, but should a failure occur in. such sequential operation, one or the other of these relays will release and will introduce a tell-tale interruption in the code being supplied to the track circuit C. That is, if any one of the counting relays ll] to I5 should fail to release within the required time as determined by the slow release interval of its associated checking .relay, the latter relay will release andwill not pick up again until the apparatus is restored to its inactive condition in which all of the counting and checking relays are deenergized. This is because the pickup circuits for relays l1 and I6 include a front contact llJoZ or lld of the respective relay Ill or II and neither of these relays can be picked up until the pickup circuit over back contacts Ilia and Ila is established for relay In to start the counting cycle. Relay It will be released by a prolonged. open circuit interval at one of the contacts lllc, l2c, or I40, whereas relay Ill will be released by a similar'prolonged opening at one of the contacts llc, I30, or I50.

When contact 5-8 closes at the third impulse of the code cycle (relay ll being energized and relay It being deenergized during the operation hereinbefore described) the following pickup circuit for relay l2 will be established: A, 6, 8, Illa down, Ila up, l2, and B. An obvious stick circuit for relay l2 will be established over contact lta down and contact I2a up as soon as relay l2 picks up. Meanwhile, relay I I will release due to opening ofits-stick circuit at contact 1-9 as Well as at back contact l2a. It will be apparent, therefore, that at the third impulse, relay I2 will be picked up and relays l0 and II will both be released. In the operation so far described,

relay It was picked up by the first impulse, relay II by the second (which released relay l0), and relay I2 by the third (which released relay ll).

Ina similar manner which will be entirely clear from the foregoing description, relays l3, l4, and I5 will be picked up by the fourth, fifth, and sixth impulses, respectively. It will be clear, therefore, that the group-of relays ID, I2, and I4 respond sequentially to the odd-numbered impulses and the group of relays II, l3, and I5 respond sequentially to the even-numbered impulses of the series within each code cycle.

At the first impulse of the succeeding code cycle (relay I5 having been picked up during the sixth impulse of the previous cycle) the following pickup circuit for relay Ill will be established: A, 6, 8, Ida down, I5a up, II), and B. From this point on, the operation for succeeding impulses is identical with that already described and will be clear without added description.

In the normal operation of the system, as soon as relays ll and- I6 pick up, impulses will be transmitted to the track circuit alternately over the upper and lower fingers of interrupter 3 controlled by the coder 4 and operating in synchronism with thefingers 6 and I which control the counting chain. The number'of such impulses depends on the number of counting relays which havea front contact (Me, Me, [2d, l3d) included in the code supply circuit. It is understood, of course, that since noimpulses can be transmitted until both checking relays l6 and n arepicked up, the full number of impulses will not be transmitted until after the initial starting cycle of the apparatus has been completed. In the ex-i; ample illustrated, relays I0, ll, l2,"and l3 each" have a contact in the code supply circuit sothat once relays I iiand ll. areboth picked up, thefirst four impulses of the code cycle will be transmitted to the track circuit, whereas the last two impulses will be blanked out. The supply circuit,

may be traced as follows: E, 110, any one of the contacts Hie, He, i211, or I3d(in definite sequen tial order), ifi upper or lower'fingerof interrupter 3, primary winding of transformer I, 2, and D. I i

Obviously, any other suitable munber of impulses could be selected for transmission to the track circuit.

I claim:

1. In a signaling system, in combination, a

signaling circuit, a source of current, a code transmitter for coding the current from said source in accordance with a predetermined pat- 1 tern, a chain of counting relays controlled by said code transmitter in such manner as normally to beoperated and released in sequence one atia time, means controlled by saidcounting chain for recurrently modifying the pattern of'said current,

a slow acting relay for checking the. sequential operation of said counting chain, said slow acting-relay having a retardation sufficient to bridge the normal operation time of a counting relay or said chain, a pickup circuit forv said slow acting relay including a contact of said code transmitter and back contacts of said counting relays; a

' holding circuit for said slow actingrelay including said code transmitter contact, said back contacts, and a front contact of said slow acting relay; and means controlled by said slow acting relay for impressing the resulting current on said signaling circuit. i 0

2. In a signaling system, in combination, a

signaling circuit, a source of current, a code transmitter for periodically coding the current from said source, a supply circuit for impressing said coded current on said signaling-circuit, a chain of counting relays controlled by said code transmitter in such manner as normally to be i operated and released in sequence one at a time,

means controlled by said counting chain and included in said supply circuit for introducing a periodic interruption in said coded current, a checking relay for checking the sequential operation of said counting chain and having a contact included in said supply circuit, said checking re lay having a retardation sufficient to bridge the normal operation time of a counting relay of said chain, a pickup circuit for said checking relay including a contact of said code transmitter and back contacts of said counting relays,and a holdnaling circuit. ing circuit for said checking relay including said t 3. code transmitter contact, saidback contacts and a front contact of said checking relay.

-3. In a signaling system, in combination, a

code transmitter for producing constantly recurring series of substantially uniform current impulses, a signaling circuit to receive said impulses, a chain of counting relays controlled by said code transmitter in such manner as normally to be operated and releasedin sequence one at a time for registering sequentially all of the impulses of saidlseries, a checking relay for checking the sequential operation of said counting chain, said checking relay having a retardation suificient to bridge the normal operation time of a counting relay of said chain, a pickup circuitffor said checking relay including a contact of said code transmitter and back contacts contact, said back contacts, and a front contact of said checking relay; and means controlledby said counting chain and by said checking relay for transmitting a selected number of said pulses to said signaling circuit. I

4. In a signaling system, in combination, a

' code, transmitter for producing constantly recurring series of substantially uniform current impulses, a signaling'circuit ,to receive said impulses, achain of counting relays controlled by said code transmitter in such manner as normally to be operated and released in sequenceone at each having a retardation sufilcient to bridge the normal operation time-of acounting relay of the respective relay group, a pickup circuit for said first checking relay including a normal contact of said code transmitter and back contacts of said first relay group; a holding circuit for said first checking relay including said normal contact, saidback contacts and, a front contact of said first checking relay; a pickup circuit forsaid v of said counting relays; a holding circuit for said: checking relay including said code transmitter second checking relay including a reverse contact of said code transmitte'nv and back contacts of said second relay group; a holding circuit for said second checking relay including said reverse conj tact, said back contacts of the second relay group,

and a front contact'of said second checking relay;

and means controlled by said counting chain and l by both of said checking relays for transmitting a selected number of said Louis Grammar;

impulses to said sis- 

